Which describes nuclear fission?(1 point)
A. starts when a neutron slams into an atom, causing the larger atom to split into two smaller atoms
B. starts when two atoms slam together, causing the larger atom to split into two smaller atoms
C. starts when a neutron slams into an atom, causing two atoms to form one, heavier atom
D. starts when two atoms slam together to form one, heavier atom
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Which describes nuclear fusion?(1 point)
A. starts when a neutron slams into an atom, causing two atoms to form one, heavier atom
B. starts when a neutron slams into an atom, causing the larger atom to split into two smaller atoms
C. starts when two atoms slam together, causing the larger atom to split into two smaller atoms
D. starts when two atoms slam together to form one, heavier atom
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What does the evidence supporting the Big Bang theory assume about the universe when it began? Select the two correct answers.(1 point)
- It was contracting
- It was composed of ice.
- It was very tiny.
- It was extremely hot.